Liquid and thin-film filters for hybrid solar energy conversion systems

Envisioning advanced solar electricity generation: Parametric studies of CPV/T systems with spectral filtering and high temperature PV

“…For the thin film reflector/ absorber arrangement typically stacks of varied refractive index materials are constructed to create the necessary spectral reflection [12,16,17,19,37,38,40]. In the direct absorption approach the working fluid in the thermal portion of the collector acts as the spectral splitter; spectrally selective is achieved either through the fluid itself [18,23] or through the suspension of small particles [20,21]. Each approach has some advantages and drawbacks that need direct comparison for guiding detailed research going forward.…”

“…2. In the thermally de-coupled case some sort of filter or spectral splitter is necessary and could be based on thin film reflector/absorber [37][38][39][40] or fluid filter [20,21,23,41]. For the thin film reflector/ absorber arrangement typically stacks of varied refractive index materials are constructed to create the necessary spectral reflection [12,16,17,19,37,38,40].…”

“…Low temperature PV/T systems have become available and widely studied [9][10][11][12][13][14][15] while CPV/T systems have seen less research due to the competing temperature demands. While CPV/T faces distinct challenges a wide variety of studies have been conducted to examine a variety of effects and applications: spectral filtering [16][17][18][19][20][21][22][23], solar cooling [24,25], fluid placement above or below the PV cell [26], thermoelectric [17,27,28], and cell bandgap and concentration ratio [29,30]. It should be noted that not all of the previous CPV/T work has looked to generate electricity from the thermal component; many are primarily using the thermal system to remove waste heat from the PV cell to improve cell efficiency and then capture medium temperature thermal energy.…”

Spectral beam splitting for efficient conversion of solar energy—A review

“…Chendo et al [88] originally proposed the concept of selective absorption by heat transfer liquids for hybrid solar collectors in 1986. Recently, Jiafei et al [89] and Otanicar et al [90] presented a numerical one dimensional heat transfer and radiation model to optimise the optical properties (absorption characteristics) of a semitransparent heat transfer fluid suitable for a direct, selective absorbing hybrid solar collector.…”

Investigation on a spectral splitting photovoltaic/thermal hybrid system based on polypyrrole nanofluid: Preliminary test

“…In addition, they should also be non-toxic, environment-friendly, and low-cost. Chendo et al [13,14] studied the spectral properties of several liquids, as well as their thermal stability at 50 C and 200 C. They found the cobalt sulfate or copper nitrate in solution, or some specific organic-based high-temperature oils could be used as liquid filter when Si cells were employed as photovoltaic unit. Otanicar [19] developed a method to determine the extinction index of liquids.…”